(Revised Abstract) Description (provided by applicant): The Cancer Center members use animal models to study tumor development and progression and treatment options for cancer. The Animal Facility is an integral part of the Shared Resources at The Wistar Institute by providing centralized service in laboratory animal medicine and husbandry. The following services are provided: 1. Review and implementation of animal protocols; 2. Centralized purchasing; 3. Complete husbandry; 4. Routine monitoring and examination of animals; 5. Animal health surveillance and veterinary care; 6. Breeding of SCID and genetically altered mice; 7. Containment of infected animals; 8. Training and technical support; and 9. Dissemination of information.